What were the scratch-and-sniff cards in EarthBound?

The EarthBound Player's Guide included six scratch-and-sniff cards, scented inserts in the spirit of the game's American marketing, which ran under the slogan This Game Stinks and used foul-smelling magazine advertisements. Five cards carried the scents of the game's world; the sixth was a contest.

The sixth card held a mystery scent. Players who thought they had identified it could write their guess on the card and mail it to Nintendo; the scent was pizza, and correct guesses earned the sender a Mach Pizza air freshener, the in-game pizza chain's delivery man Gonzales rendered as a hanging car ornament.

The cards make condition grading for the guide unusually concrete. A complete guide needs its cards present; an exceptional one needs them unscratched, their scents still sealed. Most copies that passed through 1995 the way Nintendo intended have neither.

They are also the purest surviving objects of the campaign that sank the launch: a multimillion-dollar gross-out promotion, preserved as six small cards inside a book, inside a box almost nobody bought.